A wide variety of closures are known for closing and sealing bottles and other like containers. One type of cap closure is typically provided with internal threads on its side wall portion which are adapted to engage external threads on the neck of the container for retention of the closure on the container. Rotation of the closure with respect to the container results in the closure moving axially of the bottle neck so that the closure may be removed and the container opened.
One desirable feature for closures of the above description is a provision for indicating whether the container has been previously opened by removal of the closure therefrom. To this end, various arrangements for so-called pilfer bands are known. These arrangements are sometimes referred to as tamper bands, guarantee bands, or security rings. Frequently a peripherally extending annular locking ring or other arrangement is provided on the neck of the container for interaction with the pilfer band of the closure for indication of closure tampering.
For a closure made from plastic material, it is desirable that the pilfer band be formed integrally with the shell or cap portion of the closure. When the closure is applied to a container, the integral pilfer band portion of the closure is typically brought into association with the annular locking ring or other arrangement provided on the neck of the container so that the pilfer band operatively interacts therewith for indicating whether the closure has been removed from the container.
Because the application of closures to containers is preferably performed on a high speed production line, it is desirable that application be possible with the fewest number of production steps. Heretofore, the pilfer band arrangement for some plastic closures has required one or more specific production processes for properly associating the pilfer band arrangement with the locking ring or other retaining means provided on the neck of the container.
Many of the tamper-evident closures known heretofore have limited application because of such things, for example, as the cost of making the closure or the need to provide a special container finish suitable for use with the closure.
Among the objectives of the present invention are to provide a package which has a pilfer ring that will function to indicate that the closure has been removed or tampered with, which does not require any special step in the application thereof to the container, which can be readily manufactured and which effectively provides an indication of tampering or removal of the closure.
It is another object of the present invention to provide an improved tamper-indicating seal which is relatively easy to remove from a container without requiring a tool.
Another object of the invention is to provide a tamper-evident closure that is relatively simple, provides readily observable evidence of tampering with the closure and is adaptable for use with a wide range of containers.
A further object of the invention is to provide a tamper-indicating cap and pilfer band assembly of the above type that is simple in construction, inexpensive to manufacture and highly effective in operation.